The "nested pagination with a single server roundtrip" requirement seems a little odd, I'm not sure why that's necessary or desired. I can imagine an example, a view with a list of users, then expanding one user inline to view a list of their comments. But I don't see why I'd even want this whole nested view to be returned in one round trip, it seems quite wasteful to return the first page of comments for every user before it's expanded. Do you have a better example?
The need for hitting nested “paged” data structures on first render isn’t that contrived, but I’ve never found myself needing to juggle the cursors, since you’re usually only hitting the first page for the nested ones. Loading subsequent pages would be a standalone query, rather than running the root query again with different cursors.
